Javascript Lodash代码优化/重构

这是原始JSON数据：

var data= [
      { project: "ABC",    area: 'Test',       subArea: 'Dev',     done: 10 },
      { project: "ABC",    area: 'Test',       subArea: 'QA',      done: 10 },
      { project: "ABC",    area: 'Test',       subArea: 'Support', done: 10 },
      { project: "ABC",    area: 'External',   subArea: 'Dev',     done: 5  },
      { project: "ABC",    area: 'External',   subArea: 'QA',      done: 5  },
      { project: "ABC",    area: 'External',   subArea: 'Support', done: 5  },
      { project: "ABC",    area: 'Escalation', subArea: 'Dev',     done: 20 },
      { project: "ABC",    area: 'Escalation', subArea: 'QA',      done: 20 },
      { project: "ABC",    area: 'Escalation', subArea: 'Support', done: 20 },
      { project: "ABC123", area: 'Test',       subArea: 'Dev',     done: 20 },
      { project: "ABC123", area: 'Test',       subArea: 'QA',      done: 20 },
      { project: "ABC123", area: 'Test',       subArea: 'Support', done: 20 },
      { project: "ABC123", area: 'External',   subArea: 'Dev',     done: 10 },
      { project: "ABC123", area: 'External',   subArea: 'QA',      done: 10 },
      { project: "ABC123", area: 'External',   subArea: 'Support', done: 10 },
      { project: "ABC123", area: 'Escalation', subArea: 'Dev',     done: 5  },
      { project: "ABC123", area: 'Escalation', subArea: 'QA',      done: 5  },
      { project: "ABC123", area: 'Escalation', subArea: 'Support', done: 5  },
    ];

我需要的是按项目对项目进行分组，将它们划分为区域，并对每个子区域的完成时间进行汇总。新的JSON结果必须如下所示：

    [
   {
      "name": "ABC",
      "test": {
         "total": 30,
         "totalDev": 10,
         "totalQA": 10,
         "totalSup": 10
      },
      "external": {
         "total": 15,
         "totalDev": 5,
         "totalQA": 5,
         "totalSup": 5
      },
      "escalation": {
         "total": 60,
         "totalDev": 20,
         "totalQA": 20,
         "totalSup": 20
      }
   },
   {
      "name": "ABC123",
      "test": {
         "total": 60,
         "totalDev": 20,
         "totalQA": 20,
         "totalSup": 20
      },
      "external": {
         "total": 30,
         "totalDev": 10,
         "totalQA": 10,
         "totalSup": 10
      },
      "escalation": {
         "total": 15,
         "totalDev": 5,
         "totalQA": 5,
         "totalSup": 5
      }
   }
]

_.reduce(_.filter(projectGroup, ...), sum, 0)

下面是我的实际代码，我已经得到了我想要的结果，但我认为代码可以更优化。无需重复和所有条件验证，无需硬编码映射块内的区域和子区域属性，因为这些值在服务器端是动态区域

var sum = (total, item) => total += item.done;

result = _.chain(data)
          .groupBy(function(value) { return value.project })
          .map((projectGroup, projectName) => ({ 
                  name: projectName,
                  test: {
                      total:    _.reduce(_.filter(projectGroup, (o) => ( o.area === 'Test')) , sum, 0),
                      totalDev: _.reduce(_.filter(projectGroup, (o) => ( o.area === 'Test' && o.subArea === 'Dev')) , sum, 0),
                      totalQA:  _.reduce(_.filter(projectGroup, (o) => ( o.area === 'Test' && o.subArea === 'QA')) , sum, 0),
                      totalSup: _.reduce(_.filter(projectGroup, (o) => ( o.area === 'Test' && o.subArea === 'Support')) , sum, 0)
                  },
                 external: {
                      total:    _.reduce(_.filter(projectGroup, (o) => ( o.area === 'External')) , sum, 0),
                      totalDev: _.reduce(_.filter(projectGroup, (o) => ( o.area === 'External' && o.subArea === 'Dev')) , sum, 0),
                      totalQA:  _.reduce(_.filter(projectGroup, (o) => ( o.area === 'External' && o.subArea === 'QA')) , sum, 0),
                      totalSup: _.reduce(_.filter(projectGroup, (o) => ( o.area === 'External' && o.subArea === 'Support')) , sum, 0)
                  },
                  escalation: {
                      total:    _.reduce(_.filter(projectGroup, (o) => ( o.area === 'Escalation')) , sum, 0),
                      totalDev: _.reduce(_.filter(projectGroup, (o) => ( o.area === 'Escalation' && o.subArea === 'Dev')) , sum, 0),
                      totalQA:  _.reduce(_.filter(projectGroup, (o) => ( o.area === 'Escalation' && o.subArea === 'QA')) , sum, 0),
                      totalSup: _.reduce(_.filter(projectGroup, (o) => ( o.area === 'Escalation' && o.subArea === 'Support')) , sum, 0)
                  }       
    }))

---

我不知道你想在这里优化什么，lodash应该代替你来做。我只有一句话

var sum = (total, item) => total += item.done;
function reduceData(projectGroup, projectName, comparationLabel) {
   return {
     total:    _.reduce(_.filter(projectGroup, (o) => ( o.area === comparationLabel)) , sum, 0),
     totalDev: _.reduce(_.filter(projectGroup, (o) => ( o.area === comparationLabel && o.subArea === 'Dev')) , sum, 0),
     totalQA:  _.reduce(_.filter(projectGroup, (o) => ( o.area === comparationLabel && o.subArea === 'QA')) , sum, 0),
     totalSup: _.reduce(_.filter(projectGroup, (o) => ( o.area === comparationLabel && o.subArea === 'Support')) , sum, 0)
   }
}
result = _.chain(data)
          .groupBy(function(value) { return value.project })
          .map((projectGroup, projectName) => ({ 
                  name: projectName,
                  test: reduceData(projectGroup, projectName, 'Test'),
                  external: reduceData(projectGroup, projectName, 'External'),
                  escalation: reduceData(projectGroup, projectName, 'Escalation')    
    }))

---

是的，如果要进行某种缓存，可以避免使用

.filter（projectGroup，（o）

，但这样可以节省少量的程序资源。

而不是像这样嵌套：

    [
   {
      "name": "ABC",
      "test": {
         "total": 30,
         "totalDev": 10,
         "totalQA": 10,
         "totalSup": 10
      },
      "external": {
         "total": 15,
         "totalDev": 5,
         "totalQA": 5,
         "totalSup": 5
      },
      "escalation": {
         "total": 60,
         "totalDev": 20,
         "totalQA": 20,
         "totalSup": 20
      }
   },
   {
      "name": "ABC123",
      "test": {
         "total": 60,
         "totalDev": 20,
         "totalQA": 20,
         "totalSup": 20
      },
      "external": {
         "total": 30,
         "totalDev": 10,
         "totalQA": 10,
         "totalSup": 10
      },
      "escalation": {
         "total": 15,
         "totalDev": 5,
         "totalQA": 5,
         "totalSup": 5
      }
   }
]

_.reduce(_.filter(projectGroup, ...), sum, 0)

可以这样做以防止在集合上循环两次：

_(projectGroup).filter(...).reduce(sum, 0).value()

---

为什么不在普通Javascript中使用单个循环来分组和汇总小时数

此提案使用哈希表，并按

project

属性的值进行分组

var data=[{project:'ABC'，area:'Test'，subArea:'Dev'，done:10}，{project:'ABC'，area:'Test'，subArea:'Support'，done:10}，{project:'ABC'，area:'Dev'，done:5}，{project:'ABC'，area ternal QA'，done:5}，{project:'ABC'，区域：'外部'，分区：'支持'，完成：5}，{project:'ABC'，区域：'升级'，分区：'开发'，完成：20}，{project:'ABC'，区域：'升级'，分区：'QA'，完成：20}，{project:'ABC'，区域：'升级'，分区：'支持'，完成：20}，{project:'ABC123'，区域：'测试'，分区：'开发'，完成：20}，{project:'ABC123'，区域：'Test'，分区：'QA'，完成时间：20}，{project:'ABC123'，区域：'Support'，完成时间：20}，{project:'ABC123'，区域：'External'，分区：'Dev'，完成时间：10}，{project:'ABC123'，分区：'Support'，完成时间：10}，{project:'ABC123'，分区：'Support，区域：'Escalation'，子区域：'Dev'，done:5}，{project:'ABC123'，区域：'Escalation'，子区域：'QA'，done:5}，{project:'ABC123'，区域：'Escalation'，子区域：'Support'，done:5}，
结果=[]；
data.forEach（函数（a）{
var area=a.area.toLowerCase（），
分区=‘总计’+a.分区；
如果（！此[a.项目]）{
此[a.project]={name:a.project}；
结果推送（这个[一个项目]）；
}
此[a.project][area]=此[a.project][area]|{总计：0}；
此[a.项目][区域][分区]=（此[a.项目][区域][分区]| | 0）+a.完成；
此[a.项目][区域].total+=a.完成；
}，Object.create（null））；
console.log（结果）；

---

.as控制台包装{max height:100%！important；top:0；}

.groupBy（函数（值）{return value.project}）

可以是

.groupBy（'project'））

为什么abc test totaldev=30？数字来自哪里？我编辑了，现在它是正确的。谢谢！这就是我要找的！谢谢！你的代码非常好，解决了我的问题，但我现在觉得使用Lodash更舒服。谢谢！我会做出更改。